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Redox & Isotope Biogeochemistry Group

Areal distribution of microbial sulfate reduction rates in summer
Sulfate reduction rates in coastal surface sediments during summer time


Breaking News:

In collaboration with Swiss colleagues, the research group discovers for the first time a Baertschi effect for Ba isotopes and presents a new model for oxygen isotope fractionation in the aquatic hyper-alkaline carbonate-forming environments



European Association of Geochemistry (EAG) supports Stable Isotope Session at EGU 2018 in Vienna


This year, for the seventh time since 2012, the European Association of Geochemistry (EAG) is co-organizing and supporting the session

'Application of Stable Isotopes in Biogeosciences'.


Conveneers are: Michael E. Böttcher (IOW Warnemünde), Kirstin Dähnke (HZG Geesthacht),
Gerd Gleixner (MPI Jena), Nikolaus Gussone (U Münster)





Erfolg durch Eisernen Vorhang


Auf der diesjährigen internationalen ECSA56 (Coastal Systems in Transition)-Konferenz in Bremen wurde ein Beitrag, den der IOW-Doktorand Marko Lipka aus der AG Geochemie & Isotopen-Biogeochemie vorgestellt hat, mit dem diesjährigen Posterpreis ausgezeichnet. So herausgestellt wurde das Poster mit dem Titel:

„Submarine Groundwater Discharge: A source of P and DIC for the southern Baltic Sea
and the role of an Iron Curtain“

des Autor*innenkollektivs: Lipka, Sültenfuß, Wu, Escher, Schmiedinger, Struck, Dellwig & Böttcher. Darin geht es um die Bedeutung von Grundwasser als Quelle von Phosphat und gelöstem anorganischen Kohlenstoff für die Küstengewässer der Ostsee und die Bedeutung von Eisen-Oxyhydroxid Fällungen an Quellwasser-Austritten für die Phosphat-Retention.


Happy Birthday!

2016 we are celebrating the 10th anniversary of the Geochemistry & Isotope Biogeochemistry Group at the Leibniz IOW.



Top of the Isotopes

September, 29th, 2015, University of Heidelberg: Professor Dr. Michael Böttcher, head of the Geochemistry & Isotope-Biogeochemistry Group at IOW, was elected as vice speaker of the German Association of Stable Isotope Research (GASIR) during the annual meeting. The GASIR is an association of scientists coming from diverse disciplines. All in common is the application of different stable isotope systems in research.

More informations under:


Outstanding reviewer

In June 2015, Michael Böttcher was awarded as 'Outstanding Reviewer' for the international scientific journal Earth & Planetary Science Letters.



                                                         Chemical Geology

Starting on August 1st, 2013, Prof. Dr. Michael Böttcher took the responsibility as (co) Editor-in-Chief of the renowned international scientific journal Chemical Geology. He is responsible for the fields: Biogeochemistry, Stable Isotope Geochemistry, Hydrogeochemistry, Low-Temperature Water-Rock Interactions, Carbon and Sulfur Geochemistry, and Paleoceanography.

More informations under:




The key approach of the main research activities are focuses on the process-oriented investigation (field, experiment, model) of separated and connected biogeochemical element cycles with the use of special analytical approaches as stable isotope (S, O, C, H) and redox-sensitive element partitioning (e.g., S, C, O, P, Fe, Mn, Mo). It is reflected by the main research areas:

• Stable Isotope Geochemistry

• Aquatic Geochemistry
• Sediment Geochemistry
• Environmental Geochemistry

• Experimental Geochemistry

• Mineral authigenesis (carbonates, phosphates, sulfates and sulfides)

• Proxy formation processes and application to paleo-environmental changes

• Redox and trace element biogeochemistry




Current Hot Topics:

•  Submarine Ground Water Discharge

•  Ocean Acidification

•  Phosphorous cycling

•  Mineral Authigenesis

•  Redox gradients


Current study areas:

•  Baltic Sea

•  North Sea

•  Black Sea

•  Mediterranean Sea

•  South China Sea


Analytical methods:

Aqueous solutions:

- ICP-OES (major, minor, and trace elements)

- D/H, 18O/16O, 17O/16O, and 2H and 17O-excess in water (Picarro CRDS)

- 13C/12C in DIC; 34S/32S in e.g., sulfide, sulfate; 18O/16O in sulfate (gas mass spectrometry with different inlet systems- see 'isotope fascility')

- Spectrophotometry (sulfide, iron, phosphate, sulfate, alkalinity)

- Titration analyzer with autosampler (titration alkalinity, chloride)

- Ion sensitive electrodes, laboratory and field instruments, and microsensor stand (pH, oxygen microprofiles)

- Specific conductivity, temperature

Solid phases:

- Chemical sequential extraction lines (sulfur, metal, and phosphorous species)

- D/H and 18O/16O in mineral hydrate water (Picarro CRDS - under development)

- 13C/12C in carbonates; 34S/32S in e.g., sulfides, sulfates; 18O/16O in carbonates and sulfates
  (gas mass spectrometry with different inlet systems- see 'isotope fascility')


Experimental set-ups:

- Experimental set-ups to follow low-temperature dissolution and precipitation reactions under controlled conditions of temperature and CO2-partial pressure (in particular: carbonates, sulfates, phosphates (sulfides))

- Gas mixing device (CO2 - Ar/N2)




Sampling in the German Wadden Sea.   Reference left: Al-Raei et al. (2009) Seasonal dynamics of microbial sulfate reduction in temperate intertidal surface sediments: controls by temperature and organic matter. Ocean Dynamics 59: 351–370.   doi 10.1007/s10236-009-0186-5

Right: Sampling in a Brazilian lagoon

Running projects

  MSc and BSc projects
          There are always open projects for enthusiastic MSc and BSc students.
          Please contact the group leader for further details.
          Examples for current topics are:
       -  Impact of ground water (SGD) on coastal biogeochemistry
       -  Impact of ocean acidification on benthic communities
       -  The carbonate system of marginal seas
       -  Authigenic minerals as process markers
       -  Biogeochemistry of the coupled sulfur-metal cycles in marginal seas
       -  Formation, transformation and destruction of carbonates (e.g. travertin),
       -  phosphates, sulfates, and sulfides
       -  Experimental geochemistry: Trace element and stable isotope fractionation
       -  Modeling of water-rock interactions
       -  Selected field areas: Baltic Sea, North Sea, Black Sea, Brazil, China
  • Graduate colleg Baltic TRANSCOAST (Exchange between a coastal peatland and the Baltic Sea)
    TP Biogeochemistry and SGD
    DFG (2016-2020)
    (PhD: Julia Westphal)
SECOS II (Synthesis of sediments functions in German coastal seas)
Subproject Benthic biogeochemistry and element fluxes
BMBF (2016-2019)
(Post Doc:)
  • BIOACID II (Impact of multiple stress factors associated with ocean acidification on benthic communities)
    TP Biogeochemistry
    BMBF (2012-2015)
    (PostDoc: Vera Winde)
  • SECOS (The function of sediments in German coastal seas - Evaluation of the function of marine benthic systems in the context of human impact)
    Subproject Benthic biogeochemistry and element fluxes
    BMBF (2013-2016)
    (PhD student: Marko Lipka)
    • EXCALIBOR (calibration of clumped isotopes in biogenic and authigenic carbonate-apatite)
      DFG (2014-2016)
Group leader
Group members
Dr. Olaf Dellwig (Senior Scientist)
Marko Lipka (wiss. Angest.)
Iris Schmiedinger (Technical Assistant)
Anne Köhler (Technical Assistant)
Julia Westphal (PhD student)
Anna-Katrina Jenner (MSc student)
Christine Peters (MSc student, external)
Benjamin Rach (MSc student)
Physico-chemical measurements at a carbonate spring on Rügen Island (Foto: F. Tauber)